This paper explores how contemporary Italian literature reconfigures the experience of the sacred through marginal and reclaimed landscapes. Drawing on Gilles Clément's concept of the Third Landscape—spaces excluded from systems of control and exploitation—it investigates how mountains, rural environments, and gardens become sites where forms of lived spirituality emerge beyond institutional religious frameworks. Focusing on Paolo Cognetti's Le otto montagne (2016), Matteo Melchiorre's Il Duca (2013), and Pia Pera's Al giardino non l'ho ancora detto (2016), the analysis shows how these texts depict landscapes that resist normative hierarchies and foster processes of existential negotiation. In these settings, the interaction between human experience and environment generates forms of implicit, non-institutional theology, in which the sacred is encountered through solitude, memory, care, and the awareness of mortality. Adopting a perspective informed by environmental humanities, the paper argues that contemporary Italian narrative relocates religious meaning in spaces that challenge traditional theological authority. These marginal landscapes function as alternative sites of spiritual reflection, where individual experience interrogates dominant religious discourses and articulates new configurations of belonging, ethical responsibility, and the sacred in the modern world.